Dick, engine mounts etc have been checked, wheels as well. The shaking on the jacks was very scary as the engine was trying to go around in a circles or so it seemed, front back left right vibration at the same time!!! The wheels were /are not out of shape either, they spin fine. No clunking when spun by hand, a little play in the near side passenger side shaft but felt worse. Put the car under strain though and all hell beaks loose.
The strange thing is and one that I have not had before in many years of motoring, is that no vibration is coming back to me via the steering wheel, but via the floor of the car. At it's worse, the whole car feels like it is on a rolling road vibration machine if you know what i mean? It does not feel dangerous but is very bizarre and naturally I am concerned what other damage I am doing to the car with it being driven in its present condition.
We both love the 147 mjet but reading here on the 147 forum, it (the 147) does seem to have vibration issues with one thing or another. Design or engineering shortfalls, not sure at this stage but it is strange that so may seem to have a vibration issue or one type or another don't you think?